1. Field of the Invention
The present invention relates generally to improvements in stop-bars for tapping and jig grinding units designed for use with Bridgeport-type machines.
2. Description of the Prior Art
The Tapmatic Corporation of Irvine, Calif. manufactures a reversing tapping attachment of various sizes which fit drill presses or milling machines. This tapping attachment can be used on all types of manually operated machines with rotating, nonreversing spindles. It can also be used in many applications that are automated or semiautomated, such as airfeed drill units.
The tapping attachment of Tapmatic Corporation incorporates in its design a planetary gear reverse. In order for this attachment and, specifically, the reversing mechanism of the attachment, to work, it is extremely important that the short stop arm furnished with the unit be utilized. The stop arm must engage a strong torque bar which is usually attached to either the machine quill or machine table. Neither the workpiece being tapped by the attachment nor the stop arm must be held by hand. The full power of the drilling or milling machine is transmitted to the attachment in reverse.
The torque bar that engages the stop arm of the tapping attachment must be sufficiently strong to withstand the entire force of the milling machine that is being transmitted through the tapping attachment. The torque bar mechanisms recommended by the Tapmatic Corporation for use with the tapping attachment mount the torque bar either to the machine quill or spindle, or to the torque table.
The stop-bar mechanisms recommended by Tapmatic Corporation and others in the industry restrict travel of the quill and/or maneuverability of the machine worktable.
The stop-bar mechanism of the present invention, however, provides a strong and adjustable stop-bar which will allow a machine worktable to be positioned on any coordinate of its range without interfering with, or having to adjust or relocate the stop-bar. Moreover, the stop-bar of the present invention does not restrict any spindle travel, and can be installed and removed without the use of any tools, simply and quickly.